I actually did not quite like some of the more boring near filler parts of the first two Yugioh ZEXAL arcs, I almost considered quitting it (which is super ironic considering how my username situation later ended up) after all the random profs, Nelsons, ninjas, Fortunos, Annas, digvorzhak guys etc would show up once then never again... Thankfully it got VERY good later, and even though arc 4 had some CotDs too, at least they were all linked by using the same card related to the villain. 3, 5 and 6 (especially the early cameos, and them being part of opening) were just great.